A joke walks into a bar.
The barkeep says, "You better not try anything funny in here".

An engineer, a physicist and a mathematician find themselves in an anecdote, indeed an anecdote quite similar to many that you have no doubt already heard. After some observations and rough calculations the engineer realizes the situation and starts laughing. A few minutes later the physicist understands too and chuckles to himself happily, as he now has enough experimental evidence to publish a paper. This leaves the mathematician somewhat perplexed, as he had observed right away that he was the subject of an anecdote, and deduced quite rapidly the presence of humour from similar anecdotes, but considered this anecdote to be too trivial a corollary to be significant, let alone funny.

A priest, a rabbi and a cleric are having tea. The rabbi turns to the other two and says,
"Hey, did you hear the one about us?"